g2_unpack7.c

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#include <stdio.h>
#include <stdlib.h>
#include <memory.h>
#include <string.h>
#include "grib2.h"
 
g2int simunpack(unsigned char *,g2int *, g2int,g2float *);
int comunpack(unsigned char *,g2int,g2int,g2int *,g2int,g2float *);
g2int specunpack(unsigned char *,g2int *,g2int,g2int,g2int, g2int, g2float *);
#ifdef USE_PNG
g2int pngunpack(unsigned char *,g2int,g2int *,g2int, g2float *);
#endif  /* USE_PNG */
#if defined USE_JPEG2000 || defined USE_OPENJPEG
g2int jpcunpack(unsigned char *,g2int,g2int *,g2int, g2float *);
#endif  /* USE_JPEG2000 */
 
g2int
g2_unpack7(unsigned char *cgrib, g2int *iofst, g2int igdsnum, g2int *igdstmpl,
           g2int idrsnum, g2int *idrstmpl, g2int ndpts, g2float **fld)
{
    g2int ierr, isecnum;
    g2int ipos, lensec;
    g2float *lfld;
 
    ierr = 0;
    *fld = 0;     /*NULL*/
 
    gbit(cgrib, &lensec, *iofst, 32);        /* Get Length of Section */
    *iofst = *iofst + 32;
    gbit(cgrib, &isecnum, *iofst, 8);         /* Get Section Number */
    *iofst = *iofst + 8;
 
    if (isecnum != 7)
    {
        ierr = 2;
        /*fprintf(stderr, "g2_unpack7: Not Section 7 data.\n"); */
        return ierr;
    }
 
    ipos = (*iofst / 8);
    lfld = calloc(ndpts ? ndpts : 1, sizeof(g2float));
    if (lfld == 0)
    {
        ierr = 6;
        return ierr;
    }
    else
    {
        *fld = lfld;
    }
 
    if (idrsnum == 0)
        simunpack(cgrib + ipos, idrstmpl, ndpts, lfld);
    else if (idrsnum == 2 || idrsnum == 3)
    {
        if (comunpack(cgrib+ipos, lensec, idrsnum, idrstmpl, ndpts, lfld) != 0)
        {
            return 7;
        }
    }
    else if (idrsnum == 50)
    {            /* Spectral Simple */
        simunpack(cgrib + ipos, idrstmpl, ndpts - 1, lfld + 1);
        rdieee(idrstmpl + 4, lfld, 1);
    }
    else if (idrsnum == 51)              /* Spectral complex */
        if (igdsnum>=50 && igdsnum <=53)
            specunpack(cgrib + ipos, idrstmpl, ndpts, igdstmpl[0], igdstmpl[2],
                       igdstmpl[2], lfld);
        else
        {
            fprintf(stderr, "g2_unpack7: Cannot use GDT 3.%d to unpack Data Section 5.51.\n",
                    (int)igdsnum);
            ierr = 5;
            if (lfld)
                free(lfld);
            *fld = NULL;
            return ierr;
        }
#if defined USE_JPEG2000 || defined USE_OPENJPEG
    else if (idrsnum == 40 || idrsnum == 40000)
    {
        jpcunpack(cgrib + ipos, lensec - 5, idrstmpl, ndpts, lfld);
    }
#endif  /* USE_JPEG2000 */
#ifdef USE_PNG
    else if (idrsnum == 41 || idrsnum == 40010)
    {
        pngunpack(cgrib + ipos, lensec - 5, idrstmpl, ndpts, lfld);
    }
#endif  /* USE_PNG */
    else
    {
        fprintf(stderr, "g2_unpack7: Data Representation Template 5.%d not yet "
                "implemented.\n", (int)idrsnum);
        ierr = 4;
        if (lfld)
            free(lfld);
        *fld = NULL;
        return ierr;
    }
 
    *iofst = *iofst + (8 * lensec);
 
    return ierr;    /* End of Section 7 processing */
}